Measure the stage to determine the appropriate length of curtains. Typically, curtains should be least one-and-a-half times as wide as the width of the stage. The height depends on the height of your lighting and rigging equipment. Cut curtains 8 inches taller and 6 inches wider to allow for the hem and header.
Draw the plans for your curtains. Include the height, width and number of panels. Most sets of curtains have two panels. The most common dimensions for curtains are 25 feet high by 22 feet wide.
Lay the fire-retardant fabric on the stage. Measure the fabric so that it is the appropriate height and width. Outline the shape with fabric chalk.
Cut the fabric using scissors.
Turn under 1 to 2 inches on the sides of each panel and hem raw edges using a sewing machine. Fold the top of the fabric under to at least 2 inches or as needed, and sew.
Repeat the process for the bottom, turning under for a 6 inches hem.